In the prior art, there is an electronic component device in which an electronic component is housed inside an electronic component case that an upper case is fixed on a lower case. In such electronic component device, engaging projections are provided on the side wall of the lower case, and engaging holes are provided in the side wall of the upper case. Then, the engaging projections of the upper case are engaged to the engaging holes of the lower case, thereby the lower case and the upper case are fixed.
A related art is disclosed in Japanese Laid-open Patent Publication No. 2001-321838, Japanese Laid-open Patent Publication No. 2010-258042.